Tomorrow’s coal

From
A. C. M. Laing

Fred Pearce suggests that the vegetation inundated by artificial lakes created for hydroelectric power projects will almost all decay into the atmosphere as carbon dioxide or methane (“Trouble bubbles for hydropower”, 4 May, p 28). Referring to the Balbina Dam in the Amazon catchment, the author writes&colon; “…so the reservoir was allowed to inundate more than 100 million tonnes of vegetation. As it decays most of the carbon it contains will eventually be released into the air.”

This is incorrect. I have been researching the origin of bicarbonate in the waters of the Great Artesian Basin of Australia. It …